(i) Technical Field
The present invention relates to blade driving devices and optical apparatus.
(ii) Related Art
There is known a blade driving device employed in an optical apparatus. The blade driving device is quipped with plural blades which open and close an optical path opening formed in a board. The plural blades are independently driven by plural drive sources (Japanese Unexamined Patent Application Publication No. 2006-171547).
When the plural drive sources are employed in the blade driving device, the plural drive sources are arranged as close as possible to each other, thereby reducing the whole size of the blade driving device. When the plural drive sources are arranged apart from each other, it is necessary to provide individually members housing the drive sources respectively. When the plural drive sources are arranged close to each other, a common member can house the plural drive sources, thereby reducing the size and simplifying the structure.
Each drive source includes a transmitting portion to transmit power to the blade. The transmitting portion is formed with a drive pin engaging an engagement slot formed in the blade. The driving of the drive pin causes the blade to drive.
Regarding the close arrangement of the drive sources to each other, it is conceivable that the drive pins are arranged close to each other. When a trajectory of the drive pin driving one blade overlaps the engagement slot of the other blade, however, the drive pin driving one blade engages the engagement slot of the other blade. Therefore, the blade is not operated normally. For this reason, regarding the close arrangement of the plural drive sources to each other, there are limitations in the position of the engagement slot or the swing range of the drive pin.